The Heart Outcome Prevention Evaluation (HOPE) trial demonstrated the efficacy of the angiotensin converting enzyme (ACE) inhibitor ramipril in slowing the progression of cardiovascular disease for persons with diabetes and reducing the incidence of diabetes in persons with other cardiovascular risk factors. Despite compelling findings from this randomized controlled trial, some questions remain, including the efficacy of medications with similar pharmacodynamic properties to ramipril that were not included in the HOPE study, and the efficacy of these drugs in patients who have been under-represented in clinical trials. [unreadable] The purpose of this study is to test the feasibility of using Medicare and Medicaid administrative data in conjunction with results from the HOPE trial to address these questions. We propose to: [unreadable] 1. Use causal statistical models to estimate the impact of the ACE-inhibitor ramipril on cardiovascular disease in persons with hypertension and diabetes or other coronary risk factors using Medicaid and Medicare administrative databases. [unreadable] 2. Compare the results of this model with the results for clinically similar patients who participated in the HOPE trial. If the results compare favorably, we will [unreadable] 3. Use the same statistical techniques to analyze the effectiveness of medications with similar pharmacodynamic properties to ramipril, such as other ACE-inhibitors and Angiotensin Receptor Blockers (ARBs), and to [unreadable] 4. Analyze the effectiveness of ramipril and other ACE-inhibitors and ARBs in African-American patients who were under-represented in the HOPE and other trials. The proposed study will make two important contributions. First, we will provide evidence on pharmacological therapy for persons with diabetes that can shape clinical care for a highly prevalent and burdensome disease. Second, we will develop and test a methodological framework that can be duplicated in numerous situations and may significantly enhance the utility of administrative and other secondary data sources for health outcomes research. [unreadable] [unreadable]